Commands Sketch

This sketch waits for data to arrive on the serial port. Once data arrives it is read in as a
stream until either a newline or a carriage return character is received. The data read in is then checked to
see if it matches a command. If it does the command is executed, if not the data is ignored. The sketch
then waits for more data to arrive on the serial port.

This makes the robot operate manually based upon the commands it receives.